On Jan 18, 9:34 am, Rushen Aly <[email protected]> wrote: > Thank you for your reply, > As i understand i always need to use self in spite of @ in a model
Not always, but sometimes you need to in order to resolve an ambiguity eg, if you have a local variable called foo and an accessor method called foo and you write foo then ruby needs to decide whether you wanted to call the method foo or just get the local variable. self.foo or foo() tells ruby you wanted to call the acessor method if you write foo=123, ruby will always assume you wanted to set the local variable foo, so you need to write self.foo = 123 Fred > file. I have no information about mass assignment so i am searching > for it... > Best Regards... > Rushen > > On Jan 18, 9:19 am, Frederick Cheung <[email protected]> > wrote: > > > > > On Jan 18, 6:50 am, Rushen Aly <[email protected]> wrote: > > > > Hi everybody, > > > > I am studying Ruby on Rails Tutorial: Learn Rails by Example at > > > railstutorial.org and currently i am studying chapter 7. There are > > > some issues make me confused. It will be great if you help me on these > > > issues. > > > > 1). We are creating virtual attributes via attr_accessor and making it > > > accessible via attr_accessible. Is this statement correct? I mean if > > > we create a virtual attribute via attr_accessor cant we use it > > > without declaring it with attr_accessible? > > > virtual attributes don't differ from normal attributes when it comes > > to attr_accessible: if you've gone the whitelist approach (ie you've > > used attr_accessible elsewhere), then attributes (virtual or not) are > > protected from mass assignment unless you call attr_accessible on > > them. > > > > 2). What is the difference between self.variable and @variable? Is it > > > something like that we are using self.variable for variables not > > > mentioned in attr_accesible and @variable for variables mentioned in > > > attr_accesible. Is that true? > > > self.variable calls the method called variable (which may or may not > > be backed by an instance variable), whereas @variable access the > > instance variable of that named directly. @variable won't work for an > > active record attribute, since those aren't stored in individual > > instance variables (AR stores a hash of all the database attributes in > > one place( > > > Fred > > > > Best regards... > > > Rushen -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
